Objective: Deficits in the semantic learning strategy were observed in subjects with amnestic mild cognitive impairment (aMCI) in our previous study. In the present study, we explored the contributions of executive function and brain structure changes to the decline in the semantic learning strategy in aMCI. Methods: A neuropsychological battery was used to test memory and executive function in 96 aMCI subjects and 90 age- and gender-matched healthy controls (HCs). The semantic clustering ratio on the verbal learning test was calculated to evaluate learning strategy. Medial temporal lobe atrophy (MTA) and white matter hyperintensities (WMH) were measured on MRI with the MTA and Fazekas visual rating scales, respectively. Results: Compared to HCs, aMCI subjects had poorer performance in terms of memory, executive function, and the semantic clustering ratio (P < .001). In aMCI subjects, no significant correlation between learning strategy and executive function was observed. aMCI subjects with obvious MTA demonstrated a lower semantic clustering ratio than those without MTA (P < .001). There was no significant difference in the learning strategies between subjects with high-grade WMH and subjects with low-grade WMH. Conclusion: aMCI subjects showed obvious impairment in the semantic learning strategy, which was attributable to MTA but independent of executive dysfunction and subcortical WMH. These findings need to be further validated in large cohorts with biomarkers identified using volumetric brain measurements. (JINS, 2019, 25, 706–717)

Objectives: The self-reference effect (SRE), enhanced memory for self-related information, has been studied in healthy young and older adults but has had little investigation in people with age-related memory disorders, such as amnestic mild cognitive impairment (aMCI). Self-referential encoding may help to improve episodic memory in aMCI. Additionally, self-referential processing has been shown to benefit recollection, the vivid re-experiencing of past events, a phenomenon that has been termed the self-reference recollection effect (SRRE; Conway & Dewhurst, 1995). Furthermore, it remains unclear whether the valence of stimuli influences the appearance of the SRE and SRRE. Methods: The current study investigated the SRE and SRRE for trait adjective words in 20 individuals with aMCI and 30 healthy older adult controls. Ninety trait adjective words were allocated to self-reference, semantic, or structural encoding conditions; memory was later tested using a recognition test. Results: While healthy older adults showed a SRE, individuals with aMCI did not benefit from self-referential encoding over and above that of semantic encoding (an effect of “deep encoding”). A similar pattern was apparent for the SRRE; healthy controls showed enhanced recollection for words encoded in the self-reference condition, while the aMCI group did not show specific benefit to recollection for self-referenced over semantically encoded items. No effects of valence were found. Conclusions: These results indicate that while memory for trait adjective words can be improved in aMCI with deep encoding strategies (whether self-reference or semantic), self-referencing does not provide an additional benefit. (JINS, 2018, 24, 821–832)

Memory assessment represents an important part of the clinical neuropsychologist’s duties in a geriatric context. In fact, in Canada, about one-third of seniors report memory complaints, with different causes. Based on the underlying etiology, different components of memory may be affected in older adults. Nonautobiographical retrograde memory (public or semantic) is an important aspect of memory to assess; nevertheless, there is currently no reliable and standardized clinical tool to evaluate this aspect of memory in the elderly Quebecer population. The aims of this research were therefore: (1) to develop a protocol specifically aimed at assessing non-autobiographical retrograde memory in this population, the PUB-40; (2) to obtain reference data among 105 healthy subjects; and (3) to develop a short version based on the items which discriminated a group of 20 patients with amnestic Mild cognitive impairment (aMCI) from older healthy subjects.

Amnestic mild cognitive impairment (aMCI) is the transitional, heterogeneous continuum from normal elderly to Alzheimer's disease (AD). Previous studies have shown that brain functional activity in the default mode network (DMN) is impaired in aMCI patients with saliently cognitive and memory decline. However, the effective connectivity among the spatially isolated, but functionally related areas within the DMN in aMCI patients remains largely unknown. The present study examined dysfunctional connectivity of the DMN by combining an independent component analysis (ICA) approach with multivariate Granger causality analysis (mGCA) in 18 aMCI patients and 18 age-matched cognitively normal elderly. Results from mGCA showed decreased effective connectivity occurred among the middle temporal gyrus (MTG), hippocampus (HC) and fusiform gyrus (FG), as well as between the precuneus/posterior cingulate cortex (PreCN/PCC) and HC in patients with aMCI. Such an impaired connectivity was also correlated with patients’ cognitive performance of the auditory verbal learning. Moreover, enhanced effective connectivity within frontal cortex emerged, which may maintain memory functions after attenuated connections within DMN activity. These findings may elucidate the dysfunctional processes in brain networks of aMCI patients, highlighting the importance of connectivity changes in the pathophysiology of aMCI. (JINS, 2013, 19, 1–10)

Individuals with amnestic mild cognitive impairment (aMCI) show deficits on traditional episodic memory tasks and reductions in speed of performance on reaction time tasks. We present results on a novel task, the Cued-Recall Retrieval Speed Task (CRRST), designed to simultaneously measure level and speed of retrieval. A total of 390 older adults (mean age, 80.2 years), learned 16 words based on corresponding categorical cues. In the retrieval phase, we measured accuracy (% correct) and retrieval speed/reaction time (RT; time from cue presentation to voice onset of a correct response) across 6 trials. Compared to healthy elderly adults (HEA, n = 303), those with aMCI (n = 87) exhibited poorer performance in retrieval speed (difference = −0.13; p < .0001) and accuracy on the first trial (difference = −0.19; p < .0001), and their rate of improvement in retrieval speed was slower over subsequent trials. Those with aMCI also had greater within-person variability in processing speed (variance ratio = 1.22; p = .0098) and greater between-person variability in accuracy (variance ratio = 2.08; p = .0001) relative to HEA. Results are discussed in relation to the possibility that computer-based measures of cued-learning and processing speed variability may facilitate early detection of dementia in at-risk older adults. (JINS, 2012, 18, 260–268)

To identify neuropsychological and psychosocial factors predictive of amnestic Mild Cognitive Impairment (aMCI) among a group of 94 nondemented older adults, we employed a novel nonlinear multivariate classification statistical method called Optimal Data Analysis (ODA) in a dataset collected annually for 3 years. Performance on measures of memory and visuomotor processing speed or symptoms of depression in year 1 predicted aMCI status by year 2. Performance on a measure of learning at year 1 predicted aMCI status at year 3. No other measures significantly predicted incidence of aMCI at years 2 and 3. Results support the utility of multiple neuropsychological and psychosocial measures in the diagnosis of aMCI, and the present model may serve as a testable hypothesis for prospective investigations of the development of aMCI. (JINS, 2010, 16, 721–729.)